Due to the absence of central control and the non-private nature of its network protocols, the Internet has blossomed in a decade since its opening to public access in 1990s and successfully integrated most of the existed network systems. Originally, the Internet is a representation of the network systems using Internet Protocol, however, today the Internet refers to not only the IP network systems but all kinds of network systems. The Internet may be the combination of any of the separated substantial networks which are connected with each other via a set of common protocols and logically form a single network. Recently, the technology of connecting computers and the Internet is moving fast that there is a great expansion of the bandwidth from the initial 14.4 Kbps to current 10 even 100 Mbps, ways of establishing connection have evolved from dial-up into numerous wired and wireless approaches, the development of end device is making a progress toward the mobile communication device, and currently other new ways of establishing connection with higher speed are constantly researched and developed.
In response to the popularity of computers and network devices and considerable increase of Internet users, Internet service providers (ISP for short) of all kinds of Internet-related services keep emerging. In general, ISPs provide a wide range of services which comprise connection services for enterprises and individual users like dial-up, ISDN, DSL, cable modem, leased line, as well as server co-location, email, web hosting, virtual hosting, domain name application, web page design and maintenance etc. To use said services, a user is required to apply for an account of an ISP which is then used to login to a server of the ISP before using said services via the Internet. Numerous web servers, email servers and auto-response routers are disposed at the computer facilities of an ISP which enable the connection of said servers with the router of the client through said routers so as to provide network services. So far, the main income of an ISP comes from the access service of the Internet which may be divided into two parts, the dial-up and leased line services. Besides, other value-added services like providing particular contents, electronic commerce, web page building, network advertising, hard disk leasing and other network services have also become important sources of income for ISPs. Traditionally, users access the data provided by ISPs, but as the amount of data exchanged between users increases dramatically for services like VoIP and network video surveillance etc., ISPs start providing access service for the devices used. The goal of said new kind of ISP is to provide telecommunication service without physical network that new services of VoIP and network video surveillance etc. may be available to users through said access service after network devices of the clients are connected with the Internet.
Due to limited funding and resources, usually said new kind of ISPs are incapable of providing sufficient bandwidth which results in unpleasant user experience for congestion and poor performance. To enhance the performance, said new kind of ISPs are forced to rent bandwidth from other ISPs so as to provide stable and high-speed network services. However, as the amount of users keeps increasing, either more bandwidth must be rented or more money must be invested in new facilities to ensure the constant high quality of the network environments.
Hence, for numerous ISPs, to develop a network system which enables ISPs to constantly provide high-quality network environments as the amount of users keeps increasing without renting more bandwidth or investing in new facilities has become an important objective to be achieved.